Bobbin | Structure of the Bobbin

Bobbin is a cylindrical or slightly tapered barrel, with or without flanges, for holding slubbings, rovings, or yarns.

The Structure of the Bobbin
The shape of the bobbin The tube is usually made of paperboard, plastics and has a conical shape similar to the spindle tip; the yarn is wound on the tube leaving a free space (10 ÷ 13 mm) at both ends. A full bobbin (Figure) consists of three different parts:

1.  The “H2” tapered base (kernel),
2.  The “H1”cylindrical part at the centre (yarn package or buildup),
3.  The “H” cone-shape upper end A bobbin is wound starting from the base to the tip by overlapping the various yarn layers frustrum-like; except for the kernel, this gives a conical shape to the material from the edge of the kernel to the tip of the bobbin. 

Each step of the bobbin formation consists essentially of the overlapping of a main yarn layer with a cross-wound tying layer. The main layer is wound during the slow upward travel of the ring rail; the yarn coils laid one next to the other provide the bobbin build-up. The cross layer, made of distant coils inclined downwards, is formed during the quick downward travel of the rail. This system keeps the main layers separated, in order to prevent them from being pressed one inside the other (thus resulting in a quite difficult or almost impossible unwinding of the yarn). 

Bobbin structure

The ratio between the number of yarn coils wound on the bobbin during the upward travel of the rail and the number of yarn coils wound during the downward travel usually range between 2:1 and 2.5:1 ; for this reason the rail must raise slowly (A) and lower quite quickly (B). When unwinding the bobbin at high speed (D) the simultaneous unwinding of many coils could lead to entanglements of the yarn (this does not occur in .C. case).

The yarn wound on the bobbin during each upward and downward travel of the ring rail is called run-out.; to facilitate successive unwinding, the length of the run-out ranges from 3 to 5 m and is smaller for coarse yarns and greater for finer ones. The travel of the rail is considered sufficient when it is 15÷18% larger than the 

ring spinning diameter.

The structure of the bobbin is the result of the continuous motion of the winding point of the yarn on the bobbin affected by the ring rail. The rail travels up and down along the vertical axis to form the main layers, and on the cross axis (with an upward progressive increment) to homogeneously distribute the yarn on the bobbin .

The increment value, i.e. the space between the two subsequent upward travels of the ring rail (winding cycles), determines the forming bobbin diameter with respect to two different parameters: the run-out and the yarn count.

To obtain bobbins of a given diameter it is necessary to consider that the increment is inversely proportional to the yarn count (Nm) and directly proportional to the length of the run-out; in other words, after establishing the diameter of the bobbin, with the same yarn count, when doubling the run-out length, the increment must also be doubled or, with the same run-out length, when doubling the yarn count (Nm) the increment value must be halved.

Definition and Classification of Textile Neps | Count of Neps

Any small entanglement of textile fibers that can not be unraveled, formed during carding or ginning.

Classification of Neps
For cotton fiber; there are five types of Neps. These are –

Process Neps: Commonly produced by faulty carding or up to spinning yarn.

Mixed Neps: Fibres tangle around a foreign materials. For instance – Grit.

Immature Neps: Generally form by processing immature fibre.

Homogeneous Dead Neps: A tangle of nearly all dead fibres.

Fuzz Neps: A fault of short fuzz fibers .

Count of Neps
Nep count is the no. of neps per 100 square inches of card web forming ( a standerd hank of sliver of 12 NE on a 40 inch wide card).

How To Measure the Count of Neps?
At first a web is collected from the card placed on a 10 inch × 10 inch black board. Then the neps are counted and the no. of neps found is corrected fro any difference in hank or card width.
Mathematically, Nep Count, n = m × 100 [ m = no. of neps per inch square card web].

Process Flow Chart of Textile Finishing Process

Textile finishing usually includes treatments such as scouring, bleaching, dyeing and/or printing, the final mechanical or chemical finishing operations, that during this stage are carried out on textile products (staple, sliver or top, yarns or filaments, woven or knitted fabrics) to enhance their basic characteristics like dye penetration, printability, wettability, colour, hand, and appearance.

By textile finishing, we also mean all the processing operations that, though included in the socalled finishing stage, are generally applied to the fabrics to improve their appearance, hand and properties, at times in accordance with their field of application.

The finishing stage plays a fundamental role in the excellency of the commercial results of textiles, which strictly depend on market requirements that are becoming increasingly stringent and unpredictable, permitting very short response times for textile manufacturers.

The latest machines on the market used for finishing operations generally offer multi-purpose applications; the flexibility and versatility features of these machines are uninterruptedly evolving to grant excellent consistency of the results.

Finishing operations can be carried out by means of discontinuous, continuous and semicontinuous systems.
 

Discontinuous or Batch-type Systems: 

All the operations are carried out on a single machine; it is therefore necessary to load the machine, carry out the treatments following a predetermined cycle, unload the machine and finally wash it thoroughly before starting a new cycle. This working process is extremely flexible and is suitable for processing small lots: for example, it is possible to a carry out a scouring treatment on a single machine, then a bleaching one followed by a dyeing process. For the production of large lots, the discontinuous process is labour-intensive, i.e. it requires many operators to load and unload the material; it also entails long processing times and results that can vary from one batch to another.

Continuous Systems: 

The operations are carried out by means of a series of machines; every machine carries out always and solely the same process. Every machine is assembled according to specific production requirements. A system like this entails high start-up costs and a complex setup but once the system has started, it requires a smaller staff and grants excellent repeatability and high output rates; continuous systems are therefore suitable for manufacturing large lots of products with the highest cost-efficiency.

Semi-continuous Systems: 

In these mixed systems several operations are carried out with both continuous and discontinuous machines. For example, a continuous pad-batch machine is used to wet the fabric and a discontinuous system is then used for other treatments. These mixed systems are suitable for processing small and medium lots; they require reasonable start-up costs and grant quite good reproducibility. 

The Textile Finishing Stage:

What is ERP Software? | Functions of ERP Software’s in Textile |Application of ERP Software in Textiles

ERP Software:
ERP(Enterprise Resource Planning) is revolutionary concept in the contemporary world. All the information of an enterprise under one roof for assisting planning and implementing decisions having complete visibility that is the main objective of ERP.

ERP Software’s in Textiles:
ERP Software’s are available in different sectors in textiles. Such as:

1. ERP-Software for Home Textiles
2. ERP-Software for Spinning Mills
3. ERP-Software for Weaving Mills
4. ERP-Software for Textile Processing Mills

What are the Benefits of ERP ?

1. Easily monitoring of an industry
2. Compiling report within a very short time
3. No chance for data manipulation
4. Saving of time
5. Easy access anywhere from the world

Functions of ERP Software’s in Textiles
ERP Software allows the following functions :

1. Sales order entry
2. Procurement
3. Inventory
4. Production
5. Costing
6. Managing Dye house

1. Sales Order Entry:
Considering color size combinations , creation of preformed invoice,shipping document, sales invoice, picking of finished goods, packing list generation, handling letter of credit facilities.

2. Procurement:
Requisition, approvals, purchase order creation, receiving goods through receiving documents.

3. Inventory:
Availability of raw materials/work-in progress/finished goods per lot, container, batch wise, order wise.

4. Production:
Production steps with consumption breakdown, starting and end dates, waste calculation, production progress tracking.

5. Costing:
Pre-costing by merchandisers and actual costing from raw materials in reality utilized in production floor.

6. Managing Dye House:
A lot of waste come from dyeing industry that certainly increases the fabric price. ERP software facilities dye house management providing chemical inventory, batch management system, daily production report with waste calcularion, recipe creation, lab-management, actual cost calculation, reprocess dyeing etc. in their recognized ERP system.